Fabulous shots Melaine! KUDOS!
The male cardinal does htis feeding behavior as a mating or courtship ritual. I have seen it many times but here is documentation:
http://www.wild-bird-watching....
which says in part:
At your bird feeder, one of the mating habits you may see is referred to as "mate feeding". What you'll see is the male pick up a seed, hop over to the female, and the two momentarily touch beaks as she takes the food.
Mate-feeding continues through the egg-laying and incubation phases of breeding. This behavior is actually common to many of our backyard birds. The video to the right shows an example at the nest.
Mate feeding is thought to be part of the pair bonding process. That is, it gives the female an idea of how well the male will provide food to their eventual young.
I also ran across documentation about the cardinal fighting your side rear view mirrors or windows or anything they can see their reflection in:
From:
https://www.allaboutbirds.org/...
Which says in part:
Many people are perplexed each spring by the sight of a cardinal attacking its reflection in a window, car mirror, or shiny bumper. Both males and females do this, and most often in spring and early summer when they are obsessed with defending their territory against any intruders. Birds may spend hours fighting these intruders without giving up. A few weeks later, as levels of aggressive hormones subside, these attacks should end (though one female kept up this behavior every day or so for six months without stopping).
